Aurora County, SD flood risk explained
Flood hazard in Aurora County sits at the 13th national percentile, among the lowest flood hazard in the country; driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 2 years. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Mandatory flood insurance compliance in Aurora County
Homes with a federally backed mortgage inside Aurora County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 15.4% of them do — 2 active policies against 13 structures FEMA counts in that zone, leaving a real compliance gap. Looking beyond the mandated zone, 0.1% of all residential structures in Aurora County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where Aurora County ranks
Among the 3144 US counties FEMA scores for flood hazard, Aurora County ranks 2761 — 1 being the highest hazard nationally — and 2977 by population among all 3144 counties covered here, where 1 is the largest. About 2,752 people live in Aurora County, South Dakota, spread over 708.46 square miles.
Your street may differ from Aurora County's average
3 of Aurora County's 2,938 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
Where Aurora County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. If you're unsure why any of this insurance requirement exists at all, the SFHA explainer covers it from first principles.